Very much looking forward to both.
I've been waiting ages for Zelda so I'll be focused on it first, but eventually I'll get around to Horizon.
Really, if the proximity is an issue for anyone it's probably Horizon, as the hype train for Zelda (among even those who don't own a console) is huge and media will be refocusing on it almost immediately.
Still, I think in terms of sales neither will really be affected by the other; they're must haves for people who like this sort of game and, from what I've seen, they're very different experiences.







